Control system



Patented Sept. 29, 1936 UNITED STATES PATENT OFFICE CONTROL SYSTEM Application June 1, 1931, Serial No. 541,400

22 Claims.

This invention relates to control systems, and, although it has been primarily designed for employment in connection with brake-control means on trains, its utility is by no means to be limited to such function as it is susceptible of use in other fields.

The main object and feature of the invention is the provision of means for testing or indicating the integrity of one or more circuits that control normally deenergized translating means without, however, energizing said translating means when testing the circuit or circuits.

In the accompanying drawings the invention is disclosed in several concrete and preferred forms, in which Fig. 1 is a diagrammatic view of the circuits constituting one form of the invention;

Fig. 2 is a detail view of part of Fig. 1 showing a slight modification of one of the indicating means employed in the invention;

Fig. 3 is a diagrammatic view similar to Fig. 1 but showing a modified form of the invention.

In the exemplification shown in the drawings, there are two circuits which here have one path cated by conductor C, reference characters A and B indicating line wires which in conjunction with common path C and other devices to be presently described constitute two line circuits. These line circuits may be conceived as extending from a control station D to a remote station E, and in the present instance said control station is one of a plurality of cars, such as the cab of the engine, and said remote station is another one of a plurality of cars, such as the caboose of a train. Any number of intervening cars may, of course, be present, and it will be seen that the line circuits extend from car to car. M indicates a translating device, here a traffic-controlling device such as a brakecontrol magnet, connected across conductors A and C. M indicates a similar translating device connected across conductors B and C. M and M are of the type of brake-control means that are normally deenergized, and which when energized apply the brakes. Any suitable means may be provided to energize M and W. In the present instance is shown a source of direct current 0 having one lead 0' connected to path C and the other lead 0 connected through wires 0 and o to either one or both of line conductors B and A. The arrangement is here such that when the engineers brake valve V is in the position shown in the drawings, that is in release, 55" running or holding position, the contacts are in common, said path being conveniently indiopen and no current is supplied to the line wires, but that when valve V is moved to bring contacts '0, v and 12 into engagement with contacts 12 v and 0 current is supplied to paths M and M to thereby energize them and give a service application of the brakes. When valve V is moved into an intermediate or lap position in which contacts 1; and v are in engagement with contacts 0 and 12 but in which contacts D5 and v are out of engagement, M only is energized whereby the brake application ah'eady made is maintained.

It will be understood that with such construction it is desirable to provide means for testing the integrity of the line conductors so that the engineer may be assured at all times that the brakes will function if operated. Also, on long freight trains, it is desirable that the crew in the caboose be kept informed as to the dependability of the brakes.

Accordingly, the following means, or their equivalent, are provided to test the integrity of the line circuit:

Suitable means are provided to supply to the line conductors current of a character different from that of source 0. As here shown, G indicates a generator located at the control station to supply an alternating current of a suitable frequency, say one hundred and fifty cycles, to circuit A-C. Suitable means, located at the other station, are responsive to the influence of said current to thereby produce a return indication current flow of a character difierent from that supplied by G and also by 0, said return indication flow being sent over circuit BC back to the control station. In the form of the invention here shown, the devices located at the remote station are as follows: T is a transformer, the primary of which is bridged across conductors A and C, and T indicates another transformer, the secondary of which is connected across conductors B and C and the primary of which receives energy from the secondary of T in a manner presently to be described. A tuned alternator or reed vibrator consisting essentially of tuned vibratory reed 20 and coil 2| is provided, this device being of a well-known construction and being actuated by current having a unidirectional flow. The natural period of vibration of reed 26 is here established at a frequency of thirty cycles or at some other frequency that will make the return indication current of a distinctly different character from the one-hundred-fifty cycle current supplied by G. Reed 20 when vibrating will alternately engage contacts 22 and 23 of the primary of transformer T and the secondary of said transformer will therefore impress conductors B and C with a thirty cycle alternating current. The alternating current received by the secondary of transformer T is passed through rectifier R, the alternating component in the output of the latter being here suppressed by reactor L and condenser C and unidirectional current will now pass from the upper terminal of R by way of L signal S and wire 50 to coil 2|, contact 24, reed 20, and wire 5| back to lower terminal of R. This will cause reed 20 to vibrate and will energize primary of T by current from upper terminal of R, by way of L wire 52, primary of T contact 22 or 23, reed 20 and wire 5| back to lower terminal of R. Signal or indicating device S is here a direct current slow-release relay. Any suitable means may be located at the control station to respond to the influence of the return indication current, but not to the current supplied by G or O, and these means may be here as follows: S is a signal or indicating device here consisting of a direct current relay connected across conductors B and C through the instrumentality of condenser 25, reactor 26 and rectifier 21, the condenser and reactor being tuned to the frequency of thirty cycles.

Suitable blocking or filtering means, such as are well known in the art, may be inserted in the various leads to segregate the current of source 0 from the other sources. For instance, in addition to condenser 25, there may be interposed condensers 28, 29 and 39 to prevent direct current from flowing through alternator G and the transformers, and a reactor-condenser unit 3|, or a reactor alone, may be inserted between C and source 0. So also magnets M and M can be protected from the alternating currents by having a high impedance. If it be desired to provide a more effective filter in connection with signal S, there can be used, in addition to the elements described, a second condenser 3i and a reactance 3! as shown in Fig. 2.

Assuming keys K and K to be in their closed position, it will be evident that the one-hundredfifty cycle current from G will be supplied over wires A and C and will energize primary of transformer T. This, in turn, will, through the instrumentalities described, energize signal S and supply a thirty cycle current to secondary of transformer T and to wires B and C. The indication given by S will indicate, to the crew in the caboose, the integrity of wires A and C. The return indication current will then cause signal S at the control station to be displayed, thus indicating to the engineer that wires A, B and C are in working order. It will be evident that, should either of wires A or B become impaired, signal S will not be displayed. If wire C should be broken, there might be a tendency for the current from G to fiow from A to B through magnets M and M but if that should happen such current would be too small to cause S to display a false indication because signal S and its associated elements are not responsive to current from G but only to current from T It will further be seen that by opening and closing the circuits by means of keys K and K (or intermediate keys K in the cars) messages can be sent in both directions in accordance with a prearranged code as the opening or closing of keys K and K will give indications both at S and S and the opening and closing of key K will give indications at S.

In the modification shown in Fig. 3 there is shown the same three conductors A, B, and C and the same exemplification of means to supply energy to magnets M and M as is described in connection with Fig. 1, and it is therefore unnecessary to repeat the description. The current source at the control station is here indicated by alternating current generator 32, delivering say a sixty-cycle current, connected between wires A and C whereby primary winding 33 of transformer 34 of the remote station is energized. Connected to secondary 35 of said transformer, by means of wires 36 and 31, is a rectifier 38. 39 indicates a driven code transmitter of the oscillating type having an oscillatory armature 40 normally urged in one direction by spring 4| and moved in the other direction when winding 42 is energized. Winding 42 is connected in the output circuit of rectifier 38 by means of wire 43, winding 42, wire 44, contact 45, movable contact 45, and wire I41. When winding 42 is energized the circuit is broken at contacts 45 and 46 thereby in turn deenergizing winding 42 and thereby again closing contacts 45 and 46 and so on. In addition to controlling its own energizing circuit, code transmitter 39 controls, by means of contacts 41 and 48, the circuit including wires B and C, and the mass of armature 40 and the force exerted by spring 4| are so adjusted that said armature oscillates at some resonant frequency diifering relatively widely from the sixty cycle frequency, say a frequency of three cycles per second. By these means the current received by secondary 35 from primary 33 is modulated or modified or is given a characteristic different from that of the sixtycycle current to thereby render it suitable as a return indication current having a distinct characteristic. It will be seen that in the present instance there is no separate circuit at the remote station between the line circuit composed of wires A and C and that composed of wires B and C, because, as shown, wire C is connected by means of wire 49 to secondary 35, and from the latter leads a wire 60 to contact 41, contact 48 being connected to wire B, and wires B and C being bridged at the control station by rectifier 6!. It will now be apparent that as long as secondary 35 is being energized by primary 33, the code transmitter will be actuated to send a return indication current over the following path: from secondary 35, wire 60, contacts 41 and 48, wire B, rectifier Si, wire C, and wire 49 back to secondary 35. 62 indicates a lamp, a relay or other indicating means connected in shunt between secondary 35 and wire 60, whereby as long as secondary 35 is energized by primary 33 that fact will be indicated to the crew in the caboose. 63 indicates a repeater relay at the control station or engine, said relay being energized by cur rent flow in rectifier 6| and deenergized when no current flows, and thus relay 63 is energized and deenergized in step with the opening and closing movement of contact 48, which, as we have seen, has here a frequency of three cycles per second. 64 is an armature controlled by relay 63 and this armature is picked up and released in step with the above described energization and deenergization of relay 63. Energization and deenergization of relay 63 therefore causes armature. 64 to alternately engage contacts 65 and 65 and when armature 64 engages 65 current flows from a local source 66 at the control station over wire 61, armature 64, contact 65, wire 20, through onehalf of primary winding 68 of transformer 69, wire and back to source 66. Conversely when armature 64 engages contact 65 current will flow from source 66 by way of Wire Bl, armature 56, contact 65 wire ll, through the other half of primary winding 68, wire Ti! and back to source 66. Direct current flowing alternately first through one-half and thenthrough the other half of the primary of transformer 69 induces an alternating current in secondary i2, and this alternating current is rectified by rectifier 13 to thereby energize directcurrent relay M which is of the slow-release type so that, as long as'armature i5 1 vibrates at the given frequency, said relay M will hold up the armatures controlled by it. One of said arma tures i5 is interposed in a circuit controlling indication device or lamp 15, which circuit can be traced as follows: from source 6% over wire 61,

wire ll, armature l5, wire 18, lamp l6 and wire' if! back to source 65. The other armature 19 of said relay M controls the connection between wires A and C at the power input end. When '59 is in closed position a circuit may be traced as follows: from generator 32 to wire A, primary 33, wire C, wire armature it, and wire 8| back to generator 32. It will be noted that this circuit shunts starting switch 82 in wire C so that said switch need not remain closed after the system starts operating. Condenser 83 associated with primary G8 is for the purpose of minimizing sparking at contacts 65 and 65 The operation of the system is as follows: The operator closes switch 32 thereby supplying current from generator 32 to wires A and C and primary 33. Secondary 35 being thereby energized, lamp 82 is lighted, the oscillating code transmitter is actuated, and a modulated return indication current of a character different from that supplied by generator 32 is sent over wires B and C and the connections thereof as previously described. The return indication current causes relay it to be energized thereby lighting lamp l5 and also closing the shunt between A and C around starting switch 82. may now be opened and the system will continue to function so long as the integrity of the circuits is maintained. If wire A or C breaks or the integrity of the circuits is disturbed in such a way that primary of transformer 35 receives no current from then ramp 82 will be extinguished, the code transmitter will cease operating and no return indication current will be sent back to the control station. Therefore relay 14 will become deenergized, lamp 178 will be extinguished and the power supply from generator 32 to wires A and C will be cut off. So likewise, a lack of integrity in circuit BC will deenergize relay l t, extinguish lamp l5 and disconnect the supply of power from to circuit A-C. This, in turn, will deenergiae transformer 34, lamp 62 will become extinguished and the code transmitter will cease operation. In certain circumstances a break in wire C may produce a tendency of the current from generator 32 to pass across from wire A through magnets M and lit i to wire B and thence through rectifier wire 3", contact 19, and Wire 8! to generator 32. But as this current will not have been modulated by the code transmitter, relay 14 will not energized and hence lamp '36 will become extinguished and the power supply from 32 will be cut oii with the resuits previously described.

We claim:

1. A control system a circuit extending between two lo ations, two indicating devices associated therewith each responsive to the influence of current flow therein of a char- Said starting switch acter diiferent from that to which the other indicating device is responsive and one at each end of the circuit, means at one location to continuously supply current of a certain character to said circuit'to thereby energize the indicating 5 device at the other location, and means including said first means to produce a current, which is simultaneously supplied to the circuit at said other location, to the influence of which the other indicating device is responsive.

2'. A control system including: two circuits composed of two line conductors and a common path extending between two locations, two indicating means one at each end of the two circuits to indicate the integrity thereof and each 15 responsive to the influence of current of a character different from that to the influence of which the other is responsive, means to continuously supply current to one of said circuits to energize one indicating means, and means including said first means to produce a current, which is simultaneously supplied to the other circuit, to which the other indicating means is responsive.

3. A control system including: two circuits each extending between two stations, means located at one station to continuously supply currentof a given character to one of said circuits, means located at the other station energized by current flow in said first-mentioned circuit and to thereby simultaneously produce a current flow of a different character in the other circuit, and indication means located at said one station responsive to the influence of current flow of the character supplied to the second circuit by the means located at said other station.

4. A control system including: two circuits each extending between two stations, means located at one station to continuously supply current of a given character to one of said circuits, means located at the other station energized by current flow in said first-mentioned circuit and to thereby simultaneously produce a current flow of a different character in the other circuit, indication means located at said other station re- 45 sponsive to the influence of current flow of the character supplied to the first circuit by the means located at said one station, and indication means located at said one station responsive tothe influence of current flow of the character supplied to the second circuit by the means located at said other station.

5. A control system including: a train of cars, two circuits each extending from car to car, means located in one car to continuously supply current of a given character to one of said circuits, means, located in another car responsive to the influence of current flow in said first-mentioned circuit supplied by the means in the first car, to simultaneously produce a current flow in 0 the other circuit of a character different from that supplied by the means in the first car, and indication means located in the first-mentioned car responsive to the influence of the character; of current supplied to the second circuit by the 65 means located in the second car.

' 6. A control system including: a train of cars, two circuits each extending from car to car, means located in one car to continuously supply current of a given character to one of said cir- 7o cuits, means, located in another car responsive to the influence of current flow in said first-mentioned circuit supplied by the means in the first car, to simultaneously produce a current flow in the other circuit of a character diflerent from' that supplied by the means in the first car, indication means located in the other car responsive to the infiuence of the character of current flow in the first circuit supplied by the means in the first car, and indication means located in the first car responsive to the influence of the character of current supplied to the second circuit by the means located in the second car.

7. A control system including: two circuits each extending between two stations, means located at one station to continuously supply current of a given character to one of said circuits, means located at the other station responsive to the influence of said current to thereby simultaneously produce in the other circuit a return indication current flow of a character different from that received over the first circuit from the first-mentioned station, and an indicating device located at said first-mentioned station responsive to current having the character of the return indication flow supplied to the second circuit but not effectively responsive to current of the character supplied to the first circuit.

8. A control system including: two circuits each extending between two stations and composed of two line conductors and a common path, means located at one station to continuously supply current of a given character to one of said circuits, means located at the other station responsive to the influence of said current to thereby simultaneously produce in the other circuit a retiun indication current fiow of a character different from that received over the first circuit from the first-mentioned station, and an indicating device located at said first-mentioned station responsive to current flow having the character of the return indication flow supplied to the second circuit but not effectively responsive to current of the character supplied to the first circuit.

9. A control system including: line circuit means extending between two stations, means located at one station to supply an alternating current to the line circuit means, a rectifier located at the other station to receive and rectify the alternating current received from the first station, and means located at said other station to convert the direct current of the rectifier into an alternating current of a character different from that supplied by the means at the first station and received by the rectifier at the second station and to supply it to the line circuit means to thereby provide a return indication current to the first station.

10. A control system including: line circuit means extending between two stations, means located at one station to supply an alternating current to the line circuit means, a rectifier located at the other station to receive and rectify the alternating current received from the first station, and a tuned alternator located at said other station to convert the direct current of the rectifier into an alternating current of a character different from that supplied by the means at the first station and received by the rectifier at the second station and to supply it to the line circuit means to thereby provide a return indication current to the first station.

11. A control system including: line circuit means extending between two stations, means located at one station to supply an alternating current to the line circuit means, a rectifier located at the other station to receive and rectify the alternating current received from the first station. means o a ed at said other s a n to convert the direct current of the rectifier into an alternating current of a character different from that supplied by the means at the first station and received by the rectifier at the second station and to supply it to the line circuit means to thereby provide a return indication current to the first station, and a rectifier located at the first station to receive and rectify the return indication current received from the other station.

12. A control system including: line circuit means extending between two stations, means located at one station to supply an alternating current to the line circuit means, a rectifier located at the other station to receive and rectify the alternating current received from the first station, means located at said other station to convert the direct current of the rectifier into an alternating current of a character different from that supplied by the means at the first station and received by the rectifier at the second station and to supply it to the line circuit means to thereby provide a return indication current to the first station, and indication means at the second station responsive to the influence of current flow in the output circuit of the rectifier.

13, A control system including: line circuit means extending between two stations, means located at one station to supply an alternating current to the line circuit means, a rectifier located at the other station to receive and rectify the alternating current received from the first station, means located at said other station to convert the direct current of. the rectifier into an alternating current of a character different from that supplied by the means at the first station and received by the rectifier at the second station and to supply it to the line circuit means to thereby provide a return indication current to the first station, a rectifier located at the first station to receive and rectify the return indication current received from the other station, indication means at the second station responsive to the influence of current flow in the output circuit of the rectifier located at that station, and indication means at the first station responsive to the influence of current flow in the output circuit of the rectifier located at the first station.

14. A control system including: two line circuit means extending between two stations, means located at one station to supply an alternating current to one line circuit means, two transformers located at the second station, the primary of one of which is connected to said one line circuit means and the secondary of the other of. which is connected to the other line circuit means, a rectifier the input circuit of which is connected to the secondary of the first transformer, and an interrupter connected to the output circuit of the rectifier and to the primary of the second transformer.

15. A control system including: two line circuit means extending between two stations, means located at one station to supply an alternating current to one line circuit means, two transformers located at the second station, the primary of one of which is connected to said one linecircuit means and the secondary of the other of which is connected to the other line circuit means, a rectifier the input circuit ofv which is connected to the secondary of the first transformer, a tuned alternator connected to the output circuit of the rectifier, and means including a contact operated by said tuned alternator for connecting the output circuit of the rectifier to the primary of the second transformer.

16. A control system including: two line circuit means extending between two stations, means located at one station to supply an alternating current to one line circuit means, two transformers located at the second station, the primary of one of which is connected to said one line circuit means and the secondary of the other of which is connected to the other line circuit means, a rectifier the input circuit of. which is connected to the secondary of the first transformer, an interrupter connected to the output circuit of the rectifier and to the primary of the second transformer, and an indicating device also connected to the output circuit of the rectifier.

1'7. A control system including: two line circuit means extending between two stations, moans located at one station to supply an alternating current to one line circuit means, two transformers located at the second station, the primary of one of which is connected to said one line circuit means and the secondary of the other of which is connected to the other line circuit means, a rectifier the input circuit of which is connected to the secondary of. the first transformer, a tun-ed alternator connected to the output circuit of the rectifier, means including a contact operated by said tuned alternator for connecting the output circuit of the rectifier to the primary of the second transformer, and a slowrelease indicating device connected to the output circuit of the rectifier and to an element of the tuned alternator.

18. A control system including: line circuit means extending between two stations, means located at one station to supply an alternating current to the line circuit means, means located at said other station connected with said circuit means to modify the alternating current received from the first station comprising: a transformer, the primary of which is connected to the line circuit, a rectifier the input circuit of, which is connected to the secondary of the transformer, and a code transmitter connected to the output circuit of the rectifier; and a circuit connected to the secondary of the transformer and including an indicating device and a contact controlled by the code transmitter.

19. A control system including: two line conductors and a common path, means located at one station to supply an alternating current to one of the line conductors and the common path, a transformer located at the other station the primary of which is connected between said first line conductor and the common path and the secondary of which is connected to the other line conductor, and the common path, a rectifier the input circuit of which is connected to the secondary of the transformer, a code transmitter connected to the output circuit of the rectifier, and a circuit breaker, in the connection between the secondary and the second line circuit, controlled by the code transmitter.

20. A control system including: two line conductors and a common path, means located at one station to supply an alternating current to one of the line conductors and the common path, a transformer located at the other station the primary of which is connected between said first line conductor and the common path and the secondary of which is connected to the other line conductor and the common path, a rectifier the input circuit of which is connected to the secondary of the transformer, a code transmitter connected to the output circuit of the rectifier, a cir cuit breaker, in the connection between the secondary and the second line circuit, controlled by the code transmitter, and a rectifier at the first station the input circuit of which is connected between the second line Wire and the common path.

21. A control system including: two line conductors and a common path, means located at one station to supply an alternating current to one of the line conductors and the common path, a transformer located at the other station the primary of which is connected between said first line conductor and the common path and the secondary of which is connected to the other line conductor and the common path, a rectifier the input circuit of which is connected to the secondary of the transformer, a code transmitter connected to the output circuit of the rectifier, a circuit breaker, in the connection between the secondary and the second line circuit, controlled by the code transmitter, a rectifier at the first station the input circuit of which is connected between the second line wire and the common path, and a repeater relay connected to the output circuit of the rectifier at the first station.

22. A control system including: two line conductors and a common path, means located at one station to supply an alternating current to one of the line conductors and the common path, a transformer located at the other station the primary of which is connected between said first line conductor and the common path and the secondary of which is connected to the other line conductor and the common path, a rectifier the input circuit of which is connected to the secondary of the transformer, a code transmitter connected to the output circuit of the rectifier, a circuit breaker, in the connection between the secondary and the second line circuit, controlled by the code transmitter, a rectifier at the first station the input circuit of which is connected between the second line wire and the common path, a repeater relay connected to the output circuit of the rectifier at the first station, a circuit to be opened and closed by the repeater relay, and a slow release relay controlled by said circuit.

ANDREW J. SORENSEN. LESLIE R. ALLISON. 

